Funding for this research was provided by:
National Natural Science Foundation of China (81401606, 81400862)
Science Foundation for Excellent Youth Scholars of Sichuan University (2015SU04A15)
Received: 14 August 2018
Accepted: 8 November 2018
First Online: 26 November 2018
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of the West China Hospital of Sichuan University. Written informed consent was obtained from the patients’ parents, according to the provisions of the Declaration of Helsinki.
: Written informed consent for publication this study was obtained from the patients’ parents. Copies of the signed informed consent forms are available for review by the Series Editor of BMC Pediatrics.
: The authors declare that they have no competing interests, either financial or non-financial, that could be perceived as prejudicing the impartiality of the research reported.
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